What are Ecosystem Sevices?

Ecosystems
Provide Goods and Services
We are all familiar with many of the "goods"
that natural ecosystems provide, such as food, fodder, fuelwood, timber
and medicines. It is relatively easy to calculate what these natural resources
contribute to the economy. However, most of us overlook the large number
of life-support "services" that natural ecosystems freely supply.
They are more difficult to see or to quantify, but it is these ecosystem
services that enable us to survive on Planet Earth.
Pure
Water - A Free Ecosystem Service
Nature's cycles and processes, including interactions
between plants, animals and micro-organisms, provide the ecosystem services.
Water purification is one example. The climate drives the water cycle,
which continuously purifies water through evaporation, condensation and
precipitation. A natural river system also offers water purification services.
Riparian vegetation reduces rates of soil erosion and reed beds in wetlands
slow the rate of flow of the river, allowing silt to settle out.
When natural systems break down it is costly, if
not impossible, to provide these services artificially. Furthermore, poorly
functioning ecosystems cause problems that are difficult and therefore
expensive to address. For example, destruction of the natural vegetation
along rivers causes erosion of river banks. This results in muddy water,
which is expensive to purify and in which few plants or animals can survive.
Downstream, dams become silted up, reducing water storage capacity.
Ecosystem Services are Running Down
Natural ecosystems are fairly resilient. However
all over the world, large-scale destruction of natural habitats, plants
and animals is undermining the very systems and processes upon which life
depends.
In the last fifty years we have witnessed:
- Huge losses of biodiversity, through over-harvesting
and habitat destruction.
- Disruption of nutrient cycles, through burning
of fossil fuels and excessive use of nitrogen fertilisers.
- Global climate change, resulting from increasing
levels of greenhouse gases in the atmosphere.
- Erosion and loss of fertile topsoil due to insensitive
farming and development.
- Pollution of air, water and soil, affecting the
health of people and ecosystems.
What has been responsible for these unprecedented
levels of environmental exploitation and destruction? A rapidly growing
human population, higher levels of consumption per capita and the insensitive
development and use of technology have all played a part.
A Role for Farmers
Farmers manage about 80% of South Africa's land surface
area. Through sustainable land management, farmers can make a significant
contribution to the maintenance and restoration of ecosystem processes
and services.
Ecological Restoration
Ecological restoration involves the rehabilitation
of soil, water and natural vegetation to enhance natural ecological processes.
Well functioning ecosystems automatically provide the ecosystem services
listed earlier. Because the network of nature reserves in South Africa
is inadequate, the country must also rely on its farmers to manage the
land in a sustainable manner. Farmers can guarantee the sustainability
of ecosystem services by maintaining and restoring natural habitats and
the diversity of indigenous plants and animals on their land.
Local Research
Conservation farming aims to maintain and restore
functioning ecosystems on farms, while at the same time sustaining high
levels of agricultural production. The National Botanical Institute's
Conservation Farming Project is investigating ecologically sensitive farming
practices in four regions of South Africa to find out:
- The impacts of different types of land use on the
functioning of ecosystems and on agricultural productivity.
- The benefits of conservation farming compared to
more traditional farming methods.
- Whether farmers, farm workers, local communities
and consumers in general benefit from the goods and services that these
natural areas provide.
Initial
research indicates that conservation farming provides many benefits, such
as a diverse diet for livestock, shelter for livestock (particularly during
lambing season), firewood, honey, and horticultural and medicinal plants.
As interest in the environment grows, many farmers are relying on ecotourism
to supplement their income. Game viewing, birding and flower tours are
particularly popular and all rely on well-managed natural ecosystems.
By investigating land use practices in different parts
of South Africa the Conservation Farming Project will determine which
methods are the most productive and sustainable. The project will also
develop models to estimate the economic value of ecological services provided
under these different conditions.
Counting the Cost
Ecological economics aims to quantify the value of
ecosystem goods and services to the economy. In the past we generally
took for granted both the natural resources and free services that well
functioning ecosystems provided. Development and environmental degradation
are now threatening the sustainability of ecosystems. We need to put a
monetary value to ecosystem services like pollination, natural pest control
and the mitigation of droughts and floods, in order to convince decision-makers
and developers that conservation makes good economic sense. By quantifying
the value of natural goods and services, ecological economics may help
to show more clearly the long-term costs of unsustainable development.
As yet very few studies have estimated the nature,
value and extent of natural ecosystem services - or the costs to the economy
should these services fail. We may, however, assume that the value of
these services will be high. The Conservation Farming Project aims to
estimate just how great the value of these services are to the agricultural
sector in four different natural regions of South Africa.
Fact Sheet
Click
here to view our fact sheet on ecosystem services.
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